It has been known in the art to provide various attachments which allow for the extension of at least one leg or stile of a ladder so that the ladder could be used on a sloping or irregular surface, such as a flight of stairs or the side of a hill. In the past, stile extending attachments were constructed such that the ladder had to be manufactured or modified to include special means on the ladder, such as holes drilled in the legs (stiles) of the ladder to enable mounting of the stile extending attachment thereon.
Such prior art ladder stile extending attachments are disclosed, for example, in U.S. Pat. No. 2,249,304 to Wilson or U.S. Pat. No. 2,306,797 to Biery wherein the stile extending attachments are secured to the ladder by bolts which extend through specially designated holes provided in the stiles. Therefore, these prior art attachments could not be mounted on standard ladders which were not provided with special holes adapted for receiving screws for securing a stile extending attachment to the ladder stile.